RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Vidar Berg — Mon, 17 Aug 2020 08:42:56 GMT

I need more debug information from you to be able to help find the root cause. So please do what I suggested earlier and let me know when you have new information to share.

[quote user="Somesh Burkule"]can I use it in production? or is it only used for debugging?[/quote]

This is answered in the documentation I linked to. The short answer is yes.

[quote user="Somesh Burkule"][/quote]

I am using printf() to sent transmit data to other MCU via UART.

does it affect application?

I don't think it's related to the hardfault if that's what you're asking.

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Mon, 17 Aug 2020 06:25:38 GMT

Hi Vidar Berg,

Awaiting your reply.

Thanks,

Somesh Burkule

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Fri, 14 Aug 2020 07:26:17 GMT

[quote userid="4240" url="~/f/nordic-q-a/64712/ram-reset-after-softreset-nrf52832-sdk-15-2-softdevice-6-1-0/264555"]It's a good idea to enable the HardFault handling library[/quote]

can I use it in production? or is it only used for debugging?

one more thing, I am using printf() to sent transmit data to other MCU via UART.

does it affect application? I am sending 10000bytes/500ms

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Vidar Berg — Fri, 14 Aug 2020 07:18:48 GMT

Hi,

Ok, a stack overflow or a buffer overrun sounds likely to me. It's a good idea to enable the HardFault handling library, it may help you determine what caused it. Remember to also enable debug logging, add DEBUG flag to preprocessor list, and disable compiler optimization to get as much error information as possible.

[quote user="Somesh Burkule"]today I got one point that I have not used uart flush in application anywhere. so I;ll add it now. will this affect something?[/quote]

When would you want to flush the FIFO buffer? It will just remove the received UART data you may have received from RAM.

Also, please add a check on the 'index' variable before the "UNUSED_VARIABLE(app_uart_get(&cmd_Data.raw_Data[index]));" line, in case there is a chance it may be incremented beyond the buffer size.

eg.

if ( index >= "size of raw data buffer in bytes")
{
   NRF_LOG_ERROR("Index is out of bounds with the value: %d", index");     
   APP_ERROR_CHECK(NRF_ERROR_INVALID_LENGTH);
}

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Fri, 14 Aug 2020 06:31:25 GMT

Hi Vidar Berg,

yes, I am only getting this one. I am not confirm about hardfault is due communication error or not.

Actually when I kept my device on for long time, after some time( 1-2 days or once in day )nordic not responding to other MCU. when I power OFF and ON device again it works ok.

today I got one point that I have not used uart flush in application anywhere. so I;ll add it now. will this affect something?

there may stack overflow due to that may cpu lockup but I need to confirm it.

can I enable hardfault handler? what does this do?

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Vidar Berg — Fri, 14 Aug 2020 05:54:25 GMT

Hi,

There does not seem to be anything to trigger a hardfault on APP_UART_COMMUNICATION_ERROR. Are you still able to reproduce the same stack trace you shared with Jared, or is it different now?

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Thu, 13 Aug 2020 11:22:31 GMT

Hi Vidar Berg,

please check uart callback given below:

void uart_event_handle(app_uart_evt_t * p_event)
{
   
	switch (p_event->evt_type)
    {
        case APP_UART_DATA_READY:
            UNUSED_VARIABLE(app_uart_get(&cmd_Data.raw_Data[index]));
						
            index++;
				
            if (cmd_Data.raw_Data[index - 1] == ';')
            {
								cmdRxFlg = true;
            }
						
            break;

        case APP_UART_COMMUNICATION_ERROR:
            
							//APP_ERROR_HANDLER(p_event->data.error_communication);
				
            break;

        case APP_UART_FIFO_ERROR:
				
							APP_ERROR_HANDLER(p_event->data.error_code);
				
            break;

        default:
            break;
    }
}

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Vidar Berg — Thu, 13 Aug 2020 11:13:21 GMT

Can you post your updated uart callback? A APP_UART_COMMUNICATION_ERROR does not cause a hardfault by itself.

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Thu, 13 Aug 2020 09:55:24 GMT

I tried with that also still facing an issue.

what if wrong values passed to ble stack for advertiser and scanner?

Does "APP_ERROR_HANDLER(p_event->data.error_communication);" causes hardfault?

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Vidar Berg — Thu, 13 Aug 2020 09:52:08 GMT

You can comment the "APP_ERROR_HANDLER(p_event->data.error_communication);" line in APP_UART_COMMUNICATION_ERROR event to ignore communication errors on the UART bus. This is not related to RAM initialization

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Thu, 13 Aug 2020 09:47:29 GMT

Hi,

I have issue related to nordic hardfault. I am using UART, BLE Scanner, Advertiser parallely in my application code and also fds for storing the parameters. please see below link for the issue.

https://devzone.nordicsemi.com/f/nordic-q-a/64313/hardfault-on-parallel-ble-scanning-and-advertising-on-nrf52832-with-fds-storage-sdk15-2

I suspect this may due to no RAM reset. please help me out for the same.

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Vidar Berg — Thu, 13 Aug 2020 09:39:53 GMT

Hi,

These are basic concepts that are not specific to Nordic MCUs and it's difficult to cover it one answer. It's better if you post some code to demonstrate the problem.

Globals are always initialized on startup, so it doesn't matter what the reset source is.

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Thu, 13 Aug 2020 09:25:09 GMT

Hi Vidar Berg,

Please tell me your thought about RAM reset? what does it includes?

Awaiting your reply.

Thanks,

Somesh

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Wed, 12 Aug 2020 08:59:13 GMT

Hi,

Can you please clear me that what is mean by RAM reset? which type of memory is cleared after RAM reset?

I am asking this because as per my understanding global variables are also part of RAM and they cannot be initialise again when softreset is done in nrf52832.

As I using other MCU's, they always resets RAM when there is softreset.

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Vidar Berg — Wed, 12 Aug 2020 08:07:53 GMT

How are you declaring the buffers in your code? Global variables that are not assigned a value will automatically be initialized to '0' by the startup code (before reaching main()). Anyway, memset() is a standard function you can use to clear a block of memory.

e.g.,

memset(<p_buffer>, 0, sizeof(buffer))

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Wed, 12 Aug 2020 07:51:52 GMT

Is there any way to clear it using software API?

rather best solution is to initialise all buffers at the start in main().

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Vidar Berg — Wed, 12 Aug 2020 07:42:52 GMT

As I indicated earlier, the RAM is never reset, regardless of the reset source.

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Somesh Burkule — Tue, 11 Aug 2020 13:46:44 GMT

Hi Vidar,

thanks for your quick response.

I need to clear all buffers and variables used in application code same as hardreset.

RE: RAM reset after softreset | nrf52832 | sdk 15.2 | softdevice 6.1.0

Vidar Berg — Tue, 11 Aug 2020 13:43:13 GMT

Hi,

It's usually your startup code that's responsible for re-initializing (or resetting) the RAM. Notice the statement below the table you referred to: "The RAM is never reset, but depending on reset source, RAM content may be corrupted.". Maybe you give some more background on what you are trying to achieve?